Safety fuse device



Jan. 9, 1940. w A KEE-N' 2,186,112

SAFETY FUSE DEVICE Filed Dec. 17, 1937- INVENTOR.

WILLIE H. KEEN Patented Jan. 9, 1940 UNITED STATES PATENT OFFICE 2 Claims.

The principal object of this invention is to provide a safety fire alarm system composed of a multiplicity of small economically manufactured fuses or contacts that, when subjected to heat, causes a bell or like signal to be operated.

A further object of my invention. is to provide a safety fire alarm system whereby a great number of the contact fuses may be used in order to indicate the presence of fire soon after its origin or before the flames have done a great deal of damage.

A still further object of this invention is to provide a safety fire alarm system that is extremely economical in manufacture, durable and eificient in use.

These and other objects will be apparent to those skilled in the art.

My invention consists in the constructiin, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, pointed out in my claims and illustrated in the accompanying drawing, in which:

Fig. 1 is a schematic view of my complete fire alarm system.

Fig. 2 is an enlarged end sectional view of one of the fuses or contact points used in my system.

Fig. 3 is an enlarged side plan view of one of the fuse alarms more fully illustrating its construction.

There are a great number of fire alarm systems on the market. These generally consist of spraying heads and the like placed at intervals on the ceilings of large buildings or other signal means consisting of a material having a low melting point placed at various intervals throughout a large building. These devices are too costly for use in homes and are subject to a great deal of trouble. Furthermore, these devices are unsatisfactory as they are usually placed within the room proper. Due to the cost of these various types of Systems, it is too expensive to use a great multiplicity of the units so that one of the units acts as soon as the flame starts. In other words, the unit should be placed close enough together that they will act before the flames have gained much headway. I have overcome such disadvantages and objections as will be appreciated and as are hereinafter more fully set forth.

Referring to the drawing, I have used the numeral I 0 to designate a transformer having its primary side connected to a suitable source of electric energy and having the ordinary output terminals H and I2 on its secondary side. The numeral 13 designates an electrically actuated bell or gong and having thereon the usual electrical terminals 14 and 5 as shown. The terminal M of the bell I3 is connected to the 5 terminal II of the transformer or like M by an electric lead line I6. I have used the numeral I! to designate a lead wire having one end connected to the terminal ll. of the transformer l0 and having its other end free. The numeral It designates an electric lead wire having one end connected to the terminal l5 of the bell l3 and its other end free. These wires I! and 18 extend parallel toeach other and it is between these two lead lines that I place my safety fuse that I will now describe. Each of the wires I! and I8 is bared or freed of its insulation at intervals. About this bared nortion of the wires I! and i8 is wra ped an inflammable insulative material I!) as shown in Fig. 2 of the drawing. This material can be of any type having a low flash point such as the common Celluloid. The numeral 20 designates a small spring clamp which is clamped on the outside of the material 19 as shown in Fig. 2 and which forces the wires l1 and I8 together when the material H! has been melted or burned from between and around the wires l1 and I8. This clamp 20 may have teeth on its inner side for more securely holdin the material I9 and wires I! and It in the correct position and for assuring a positive contact between the wires I! and !8 when the material H! has been burned from about the wire. The practical operation of my device is as follows:

The terminal ll of the transformer l0 and the terminal [4 of the bell It being connected with the electric lead line It provides one side of the source of power to the bell 13. One end. of the wire I! is connected to the terminal !2 of the transformer l0 and one end of the wire I8 is connected to the terminal !5 of the hell it and a plurality of the fuse elements consisting of a bared portion of the wires I! and 28. the inflammable material and the clamp 20 are imposed between these parallel lead lines. These fuses may be placed at intervals throughout the walls of a dwelling or the like and should be spaced closely together in order that the signal be sounded at the start of the confiagration. Should a fire start, the inflammable material I9 will be burned from its position about the wires I1 and I8 and the spring action of the clamp will force the wires l1 and [8 together at the point where they are bared and the clamp itself will contact the two wires l1 and 18, thereby completing the other side or electrical connection between the terminal of the transformer Ill and the terminal l5 of the bell or gong l3, thereby causing the alarm or hell l3 to be actuated and sounding a warning. Obviously the fuse portions may be separate units and may be individually mounted and connected in the wiring circuit and, due to an extremely economical structure, a. great number of these fuse elements may be utilized to assure the actuation of an adequate warning device before a fire obtains a great deal of headway in the structure being protected. Thus I have provided a safety fire alarm systemv that fulfills my objects, overcomes the disadvantages of prior fire alarm systems and which provides fuse units of small compact structure easily placed, fool-proof, and positive in operation.

Some changes may be made in the construction and arrangement of my improved safety fire alarm system without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

I claim:

1. In a fuse for fire alarm systems, two metallic electrical conductors adjacent each other, an insulative inflammable material about said electrical conductors and a spring clamp means for holding said electrical conductors and said insulative material in position.

2. In a fuse for fire alarm systems, two metallic electrical conductors adjacent each other, an insulating meltable material about and between said electrical conductors, and a spring clamp means embracing said insulating meltable material and said electrical conductors for holding them in position.

WILLIE A. KEEN. 

